The overall objective of this program is the development of an inexpensive remote microwave respiration monitor for use in recovery rooms and concentrated care units that will reduce the need for sensor attachment to the patient. Using advanced microwave techniques that incorporate passive transponders to eliminate the artifacts and false alarms that plague typical microwave motion sensors, the proposed instrument will provide continuous respiration rate information even in the presence of motion and activity nearby the patient. The use of battery- operated versions the instrument may be extendable to patients being transported exigently on operating room gurnies or in ambulances or to those suffering superficial trauma where sensor attachment would be painful. It is the specific aim of Phase I to design a proof-of-concept model of such an instrument leading to the eventual design of a practical commercial model.